In recent years, 3D geometric models of the heart are used in education, simulation and the like. For example, grasping the three dimensional shape from a collection of tomographic images such as Computed Tomography (CT) images or Magnetic Resonance Imaging (MRI) images requires much experience and knowledge, however, by generating and displaying a 3D geometric model, it becomes possible for even a person with little medical knowledge to intuitively recognize the shape of the heart.
Incidentally, there are the following kinds of methods for generating a 3D geometric model of the heart. For example, as illustrated in FIG. 1, first, a physician draws boundary lines of the inner wall section of the heart muscle, the outer wall section of the heart muscle, blood vessels and the like on several hundred tomographic images, and specifies the respective parts' names. After that, the physician looks at the 3D shape according to information concerning the boundary lines and parts, gives instructions for corrections, and forms the 3D geometric model according to the correction instructions. As necessary, the physician divides the formed 3D geometric model into polygons. Incidentally, there are a lot of variations among patients for the heart position and angle and the ratio of the heart ventricles and heart atrium, and there are also differences depending on the clinical condition of a patient. Therefore, it is necessary to generate a 3D geometric model for each patient, which is close to the actual heart shape of the patient.
However, the heart is surrounded by many blood vessels, surrounding organs, bone and the like, and has a complex structure of heart muscles having different thicknesses depending on the part. In addition to those problems, there are also differences among individuals. Therefore, grasping the 3D positional information from tomographic images requires experience and knowledge in anatomy. Moreover, there are also cases in which it is difficult to distinguish boundaries due to unevenness in contrast dye or surgical scars. Therefore, except for a skilled physician, it is difficult to identify boundaries of the heart muscles, blood vessels and the like from tomographic images.
As described above, in conventional methods, in order to generate a 3D geometric model of the patient's heart, a physician having knowledge had to draw boundary lines on several hundred tomographic images. Therefore, a lot of works as well as knowledge are required.